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Swimming and rafting of E.coli microcolonies at air-liquid interfaces.

ABSTRACT: The dynamics of swimming microorganisms is strongly affected by solid-liquid and air-liquid interfaces. In this paper, we characterize the motion of both single bacteria and microcolonies at an air-liquid interface. Both of them follow circular trajectories. Single bacteria preferentially show a counter-clockwise motion, in agreement with previous experimental and theoretical findings. Instead, no preferential rotation direction is observed for microcolonies suggesting that their motion is due to a different physical mechanism. We propose a simple mechanical model where the microcolonies move like rafts constrained to the air-liquid interface. Finally, we observed that the microcolony growth is due to the aggregation of colliding single-swimmers, suggesting that the microcolony formation resembles a condensation process where the first nucleus originates by the collision between two single-swimmers. Implications of microcolony splitting and aggregation on biofilm growth and dispersion at air-liquid interface are discussed.

SUBMITTER: Sinibaldi G

PROVIDER: S-EPMC5822344 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature

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Swimming and rafting of E.coli microcolonies at air-liquid interfaces.

Sinibaldi Giorgia G Iebba Valerio V Chinappi Mauro M

MicrobiologyOpen 20171022 1

The dynamics of swimming microorganisms is strongly affected by solid-liquid and air-liquid interfaces. In this paper, we characterize the motion of both single bacteria and microcolonies at an air-liquid interface. Both of them follow circular trajectories. Single bacteria preferentially show a counter-clockwise motion, in agreement with previous experimental and theoretical findings. Instead, no preferential rotation direction is observed for microcolonies suggesting that their motion is due t ...[more]

PMID: 29057610

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